
FRP 24: Exhaust Air Thermistor Replacement
AC Repair and Adjustment Procedures
140
Cray Research/Silicon Graphics Proprietary
HMM-168-A
5.
Secure the sensor plate with the four #2 Phillips screws.
6.
Open the blower circuit breaker (CB8) and the power supply circuit
breakers (CB2 through CB7).
7.
Power up the cabinet and verify proper thermistor function:
a. With the WACS on, and the blower and power supplies off, check the
temperatures on the WACS display to ensure that the new thermistor
provides normal readings.
b. If a heat gun is available, use it to apply heat to the new thermistor, and
check the temperature change on the WACS display.
8.
Remove power from the cabinet.
9.
Replace the upper plenum panel and the module panel.
10. Replace the blower exhaust shield and attach the cable to the clock switch
board.
11. Return the cabinet to normal operation, and close both cabinet doors.
WARNING
Ensure that the blower circuit breaker
is open and that the blower is not
spinning. Failure to do so could result
in severe injury.
WARNING
The thermostats receive line voltage.
Do not contact them. Failure to avoid
the thermostats and thermostat wires
could result in severe shocks and
burns.